266040865 has 4 divisors (see below), whose sum is σ = 319249044. Its totient is φ = 212832688.

The previous prime is 266040823. The next prime is 266040877. The reversal of 266040865 is 568040662.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 70963776 + 195077089 = 8424^2 + 13967^2 .

It is a cyclic number.

It is not a de Polignac number, because 266040865 - 2⁷ = 266040737 is a prime.

It is a Duffinian number.

It is a nialpdrome in base 16.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 26604082 + ... + 26604091.

It is an arithmetic number, because the mean of its divisors is an integer number (79812261).

Almost surely, 2^266040865 is an apocalyptic number.

It is an amenable number.

266040865 is a deficient number, since it is larger than the sum of its proper divisors (53208179).

266040865 is an equidigital number, since it uses as much as digits as its factorization.

266040865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 53208178.

The product of its (nonzero) digits is 69120, while the sum is 37.

The square root of 266040865 is about 16310.7591791431. The cubic root of 266040865 is about 643.1556913007.

The spelling of 266040865 in words is "two hundred sixty-six million, forty thousand, eight hundred sixty-five".